This disclosure relates to methods of servicing a wellbore. More specifically, it relates to methods of treating a wellbore with sealant compositions.
Natural resources such as gas, oil, and water residing in a subterranean formation or zone are usually recovered by drilling a wellbore down to the subterranean formation while circulating a drilling fluid in the wellbore. After terminating the circulation of the drilling fluid, a string of pipe, e.g., casing, is run in the wellbore. The drilling fluid is then usually circulated downward through the interior of the pipe and upward through the annulus, which is located between the exterior of the pipe and the walls of the wellbore. Next, primary cementing is typically performed whereby a sealant composition (e.g., cement slurry) is placed in the annulus and permitted to set into a hard mass (i.e., sheath) to thereby attach the string of pipe to the walls of the wellbore and seal the annulus. Subsequent secondary cementing operations may also be performed.
During the life of a wellbore, sealant compositions (e.g., cements) are typically subjected to a wide variety of conditions (e.g., varying pressure and thermal ranges, cyclical changes in underground pressures and temperatures during production and shut-in stages, etc.), which may cause cracks and fractures in the sealant compositions (e.g., cements). To help alleviate this problem, conventional reinforcing materials may be added to wellbore sealant compositions (e.g., cements). However, once a crack forms in the sealant composition (e.g., cement), the changes in the wellbore environment (e.g., wellbore pressure and temperature), along with sustained reservoir pressures, may cause sealant composition (e.g., cement) fracturing and crack propagation by tensile and/or compressive failures within the sealant composition (e.g., cement). While conventional reinforcing materials help prevent to a certain extent the initiation of cracks and fractures in sealant compositions (e.g., cements), no conventional reinforcing materials commonly used in wellbore servicing operations help prevent fracturing, crack propagation, and failure after the initiation of cracks and fractures in sealant compositions (e.g., cements). Thus, an ongoing need exists for more effective compositions and methods of using sealant compositions in wellbores and/or subterranean formations.